The Juventus playmaker scored a stunning free kick during a desperately one-sided friendly in Bologna, while Andrea Poli, Alberto Gilardino and Alberto Aquilani also netted
Andrea Poli broke the deadlock - and his international duck - with a smart finish before Alberto Gilardino struck his first goal for the Azzurri since 2010 shortly before the interval.
Andrea Pirlo added a stunning free kick in early stages of the second half and set up Italy's fourth with another set-piece that led to Alberto Aquilani converting from close range with just over 10 minutes remaining.
Pirlo had been the best player on the pitch all evening, playing a key role in Italy dominating possession and territory right from the first whistle.
However, Aldo Junior Simoncini was in inspired form early on, denying Giacomo Bonaventura from close range, after the Atalanta man had latched onto a knockdown from Luca Antonelli, before pulling off an even better stop to thwart Alberto Aquilani, who must have thought that he had scored after connecting with a Pirlo cross just six yards out.
The Azzurri had the ball in the net moments later, but Christian Maggio was stood in an offside position when he stroked home from two yards out, seconds after Simoncini had pulled off another great stop, this time from Alessandro Diamanti.
Italy had another goal disallowed at the midway point of the first half, with Alberto Gilardino having failed to sufficiently check his run before turning in a low cross from Bologna team-mate Diamanti.
Gilardino did nearly everything right in the 25th minute, demonstrating fine technique in volleying Maggio's right-wing cross goalwards, but Simoncini saved once again, before gathering the loose ball at the second attempt.
It was clear that a goal was coming, though, and it belatedly arrived 27 minutes in when Poli pounced on a loose ball on the edge of the area, lifting it over a trailing leg before coolly firing through the legs of Simoncini.
Cesare Prandelli's men doubled their advantage 10 minutes later, Gilardino finally getting the goal he was so desperately craving when he was on hand to follow up, after Aquilani had drawn another wonderful reaction save out of Simoncini.
Italy unsurprisingly rung the changes in the second half, but it did little to upset their rhythm and they went three up courtesy of the most pinpoint 30-yard free kick from Pirlo five minutes after the break.
Mario Balotelli, who had taken over up front from hometown hero Gilardino, nearly repeated the trick on 65 minutes, but his low strike around the San Marino wall came back off the post.
However, Italy would get a fourth on 79 minutes when Aquilani deservedly got his name on the scoresheet by tapping home from barely a yard out, after San Marino's substitute goalkeeper Federico Valentini had failed to hold another Pirlo set piece.
Balotelli very nearly added a fifth but he fired wide after a powerful surge from deep before then heading an Ignazio Abate cross against the bar.
As it was, Italy had to settle for just the four goals in a routine win that sets them up nicely for next weekend's trip to Prague.